Processing aspects of MOD strontium titanate buffer layers for coated conductor applications

Recent trends in HTS research have been geared toward development of coated conductors. In these conductors, a flexible metallic substrate, typically a nickel alloy, is covered successively with one or more thin buffer layers such as YSZ, STO, MgO, etc., and a relatively thick film of Y123. To make the fabrication of such conductors scalable and cost effective, this paper demonstrates the application of a solution based metallorganic decomposition (MOD) process for deposition of strontium titanate buffer layers. We present results on the effect of precursor chemistry and heat treatment variables on the densification behavior, texture, and microstructure of the strontium titanate films. Highly oriented strontium titanate films with good coverage across the substrate surface have been processed using this method. Thus, this process offers promise to the application of scalable solution deposition techniques to coated conductor fabrication. (C) 2002 Published by Elsevier Science B.V.